/**
 * Copyright (c) 2014 - 2017, Nordic Semiconductor ASA
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 * All rights reserved.
 * 
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 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 * 
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 * 
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 * 
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 * 
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
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 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
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/**
 * @file
 * @brief ADC HAL implementation
 */

#include "nrf_adc.h"

#ifdef ADC_PRESENT

/**
 * @brief Function for configuring ADC.
 *
 * This function powers on ADC and configures it. ADC is in DISABLE state after configuration,
 * so it should be enabled before using it.
 *
 * @param[in] config  Requested configuration.
 */
void nrf_adc_configure(nrf_adc_config_t * config)
{
    uint32_t config_reg = 0;

    config_reg |= ((uint32_t)config->resolution << ADC_CONFIG_RES_Pos) & ADC_CONFIG_RES_Msk;
    config_reg |= ((uint32_t)config->scaling << ADC_CONFIG_INPSEL_Pos) & ADC_CONFIG_INPSEL_Msk;
    config_reg |= ((uint32_t)config->reference << ADC_CONFIG_REFSEL_Pos) & ADC_CONFIG_REFSEL_Msk;

    if (config->reference & ADC_CONFIG_EXTREFSEL_Msk)
    {
        config_reg |= config->reference & ADC_CONFIG_EXTREFSEL_Msk;
    }

    /* select input */
    nrf_adc_input_select(NRF_ADC_CONFIG_INPUT_DISABLED);

    /* set new configuration keeping selected input */
    NRF_ADC->CONFIG = config_reg | (NRF_ADC->CONFIG & ADC_CONFIG_PSEL_Msk);
}


/**
 * @brief Blocking function for executing single ADC conversion.
 *
 * This function selects the desired input, starts a single conversion,
 * waits for it to finish, and returns the result.
 * ADC is left in STOP state, the given input is selected.
 * This function does not check if ADC is initialized and powered.
 *
 * @param[in] input Requested input to be selected.
 *
 * @return Conversion result
 */
int32_t nrf_adc_convert_single(nrf_adc_config_input_t input)
{
    int32_t val;

    nrf_adc_input_select(input);
    nrf_adc_start();

    while (!nrf_adc_conversion_finished())
    {
    }
    nrf_adc_conversion_event_clean();
    val = nrf_adc_result_get();
    nrf_adc_stop();
    return val;
}
#endif
